Total Bioaerosol Detection by a Succinimidyl-Ester-Functionalized Plasmonic Biosensor To Reveal Different Characteristics at Three Locations in Switzerland

Abstract

Bioaerosols consisting of biologically originated airborne particles such as microbes, metabolites, toxins, and fragments of microorganisms are present ubiquitously in our living environment. The international interests in bioaerosols have rapidly increased because of their many potential health effects. Thus, accurate and fast detection of total bioaerosols in different environments has become an important task for safeguarding against biological threats and broadening the pool of bioaerosol knowledge. To quickly evaluate the total bioaerosol concentration, we developed a localized surface plasmon resonance biosensor based on succinimidyl-ester-functionalized gold nanoislands (SEF–AuNIs) for quantitative bioaerosol detection. The detection limit of our proposed SEF–AuNI sensors for model bacteria Escherichia coli and Bacillus subtilis can go to 0.5119 and 1.69 cells/mL, respectively. To demonstrate the capability of this bioaerosol sensing technique, we tested aerosol samples collected from Bern (urban station), Basel (suburban station), and Rigi mountain (rural and high altitude station) in Switzerland and further investigated the correlation with endotoxin and PM10. The results substantiated that our SEF–AuNI sensors could be a reliable candidate for total bioaerosol detection and air quality assessment.

Dual-Functional Plasmonic Photothermal Biosensors for Highly Accurate Severe Acute Respiratory Syndrome Coronavirus 2 Detection

“…Thus, based on the LSPR signal−target size relationship, the estimated LoD for detecting the entire RNA strands from SARS-CoV-2 could be approximately 2.26 × 10 4 copies. 38 A recent study reported the viral loads of SARS-CoV-2 from different respiratory trace samples including the throat/nasal swabs and the sputum. Based on these clinical specimens collected from 82 infected individuals, the overall viral load soon after onset was higher than 1 × 10 6 copies/mL.…”

Recent Development of Optofluidics for Imaging and Sensing Applications

“…In addition to optical components, functional photonic nanostructures have also been incorporated within optofluidic devices for the signal transduction in biochemical sensing. For example, Qiu et al and Funari et al coated the glass substrate with gold islands by dewetting [52][53][54] and gold nanospikes by electrodeposition [55], respectively. The glass slides were then bounded with Teflon or PDMS microfluidics, while the gold islands and nanospikes were further functionalized for localized surface plasmon resonance (LSPR)based biosensing.…”

“…[91] The nanostructured end-face was inserted into a microfluidic channel for real-time biosensing and the reported limit of detection was found to be 0.1 pg/mL. Qiu et al proposed a strategy for the measurement of total bioaerosol-based LSPR [53], as shown in Figure 9b. The gold nanoislands were functionalized with succinimidyl ester, which can detect the bioaerosols by chemically reacting with the amine group.…”

Scalable, Lithography-Free Plasmonic Metasurfaces by Nano-Patterned/Sculpted Thin Films for Biosensing

“…These "half" antibodies can be directly covalent immobilized to the gold surface, taking advantage of the thiol groups simplifying the creation of the biointerfaces, and enhancing the biodetection sensitivity by decreasing the biorecognition events thickness. In environmental analysis, Qiu et al (2020) have recently demonstrated the detection of total bioaerosols from real samples obtained in different locations around Switzerland. Bioaerosols are a complex mixture of viruses, toxins, and allergens, with a relevant influence on human health.…”